Mechanics Lecture 4, Slide 1 - PowerPoint PPT Presentation

1 / 16
About This Presentation
Title:

Mechanics Lecture 4, Slide 1

Description:

Physics 2210 Lecture 4 Today's Concepts: Newton s Laws a) Acceleration is caused by forces b) Force changes momentum c) Forces always come in pairs – PowerPoint PPT presentation

Number of Views:43
Avg rating:3.0/5.0
Slides: 17
Provided by: Mich767
Category:

less

Transcript and Presenter's Notes

Title: Mechanics Lecture 4, Slide 1


1
Physics 2210Lecture 4
  • Today's Concepts Newtons Laws
  • a) Acceleration is caused by forces
  • b) Force changes momentum
  • c) Forces always come in pairs
  • d) Good reference frames

2
Newtons 2nd Law
Acceleration is caused by force.
A bigger mass makes this harder
3
Checkpoint
  • The net force on a box is in the positive x
    direction. Which of the following statements best
    describes the motion of the box
  • A) Its velocity is parallel to the x axis
  • B) Its acceleration parallel to the x axis
  • C) Both its velocity and its acceleration are
    parallel to the x axis
  • D) Neither its velocity or its acceleration need
    be parallel to the x axis

4
(No Transcript)
5
ACT
  • A force F is applied to a small block, that
    pushes a larger block. The two blocks accelerate
    to the right. Compare the NET FORCE on the block
    with mass M, to the net force on the block with
    mass 5M.
  • A) FM lt F5M
  • B) FM F5M
  • C) FM gt F5M

a
5M
F
M
6
Checkpoint
  • You are driving a car with constant speed around
    a horizontal circular track. The net force acting
    on your car
  • A) Points radically inward toward the center of
    the circular track
  • B) Points radically outward, away from the
    center of the circular track
  • C) Points forward in the same direction your car
    is moving
  • D) Points backward, opposite to the direction
    your car is moving
  • E) Is zero.

7
Aside Centripetal acceleration and force
  • 1) Objects moving in a circle always have a
    component of acceleration, called centripetal,
    which is toward the center of the circle.
  • 2) Centripetal acceleration must be caused by a
    force
  • Friction, gravity whatever force keeps it
    moving in a circle.
  • This force is often called the centripetal
    force
  • 3) There is no new kind of force here.
  • 4) There is no such thing as centrifugal force.

They can have also have tangential acceleration
if their speed is not constant
8
(No Transcript)
9
Momentum Force
10
Checkpoint
  • You are driving a car with constant speed around
    a horizontal circular track. The momentum of your
    car
  • A) Points radically inward toward the center of
    the circular track
  • B) Points radically outward, away from the center
    of the circular track
  • C) Points forward in the same direction your car
    is moving
  • D) Points backward, opposite to the direction
    your car is moving
  • E) Is zero.

11
(No Transcript)
12
(No Transcript)
13
Newtons 1st Law
Ice-puck
Fake Forces Coriolis (YouTube)
14
Newtons 3rd Law
Forces come in pairs!
Fire-cart
15
ACT
  • A small guy and a large football player moving at
    the same speed collide head-on. Which person
    experiences the larger force during the collision?

A) The small guy. B) The football player. C) They
experience the same force.
16
(No Transcript)
Write a Comment
User Comments (0)
About PowerShow.com